Logging device for drug delivery device

ABSTRACT

An add-on logging device (100, 300) mounted to a drug delivery device is turned on when the cap is removed. After a given amount of time in inactivity the sensor means of the add-on device is turned off automatically to save energy. If the user takes a dose of drug this is not detected as the add-on device is only turned on when the cap is removed. According to the present invention a warning message is provided when the cap is re-mounted after the sensor means has been turned off automatically, the warning message indicating to a user that an expelled dose may not have been detected.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is an Application for Reissue of U.S. Pat. No.10,159,797, issued Dec. 25, 2018 (U.S. application Ser. No. 15/315,414,filed Dec. 1, 2016); which is a 35 U.S.C. § 371 National Stageapplication of International Application PCT/EP2015/062499 (published asWO 2015/185687), filed Jun. 4, 2015, which claims priority to EuropeanPatent Application 14171456.8, filed Jun. 6, 2014; the contents of whichare incorporated herein by reference.

The present invention generally relates to medical devices for which thegeneration, collecting and storing of data are relevant. In specificembodiments the invention relates to devices and systems for capturingand organizing drug delivery dose data in an efficient and user-friendlyway.

BACKGROUND OF THE INVENTION

In the disclosure of the present invention reference is mostly made todrug delivery devices used e.g. in the treatment of diabetes by deliveryof insulin, however, this is only an exemplary use of the presentinvention.

Drug injection devices have greatly improved the lives of patients whomust self-administer drugs and biological agents. Drug injection devicesmay take many forms, including simple disposable devices that are littlemore than an ampoule with an injection means or they may be durabledevices adapted to be used with pre-filled cartridges. Regardless oftheir form and type, they have proven to be great aids in assistingpatients to self-administer injectable drugs and biological agents. Theyalso greatly assist care givers in administering injectable medicines tothose incapable of performing self-injections.

Performing the necessary insulin injection at the right time and in theright size is essential for managing diabetes, i.e. compliance with thespecified insulin regimen is important. In order to make it possible formedical personnel to determine the effectiveness of a prescribed dosagepattern, diabetes patients are encouraged to keep a log of the size andtime of each injection. However, such logs are normally kept inhandwritten notebooks, from which the logged information may not beeasily uploaded to a computer for data processing. Furthermore, as onlyevents, which are noted by the patient, are logged, the note book systemrequires that the patient remembers to log each injection, if the loggedinformation is to have any value in the treatment of the patient'sdisease. A missing or erroneous record in the log results in amisleading picture of the injection history and thus a misleading basisfor the medical personnel's decision making with respect to futuremedication. Accordingly, it may be desirable to automate the logging ofejection information from medication delivery systems based on theassumption that ejected doses corresponds to injected doses.

Though some injection devices integrate this monitoring/acquisitionmechanism into the device itself, e.g. as disclosed in US 2009/0318865and WO 2010/052275, most devices of today are without it. The mostwidely used devices are purely mechanical devices either durable orprefilled. The latter devices are to be discarded after being emptiedand so inexpensive that it is not cost-effective to build-in electronicdata acquisition functionality in the device itself. Addressing thisproblem a number of solutions have been proposed which would help a userto generate, collect and distribute data indicative of the use of agiven medical device.

For example, WO 2007/107564 describes an electronic “add-on” moduleadapted to be attached to and measure signals generated by a standardmechanical pen device, the module relying on e.g. the sounds inherentlyproduced by such a device during operation. WO 2010/037828 discloses afurther add-on module adapted to be mounted on a pen device and create atime log for data representing sizes of doses expelled by the drugexpelling mechanism of the pen device.

Alternatively, in order to provide pre-filled drug delivery deviceswhich more reliably allow detection of an out-dosed amount of drug, ithas been proposed to modify such pre-filled drug delivery devices toprovide them with structures making them more suitable for cooperationwith external detection means, thereby providing more reliable andaccurate determination of out-dosed drug amounts. For example,PCT/EP2012/069729 discloses a drug delivery device in which a rotatingpiston rod is provided with a magnet allowing an add-on logging moduleto detect the axial position of the magnet by means of 3D magnetometers.

Having regard to the above, it is an object of the present invention toprovide systems, devices and methods allowing capturing and organizingdrug delivery dose data in an efficient and user-friendly way.

DISCLOSURE OF THE INVENTION

In the disclosure of the present invention, embodiments and aspects willbe described which will address one or more of the above objects orwhich will address objects apparent from the below disclosure as well asfrom the description of exemplary embodiments.

Thus, in a general aspect of the invention a logging device is provided,the logging device being adapted to be releasably attached to a drugdelivery device or being formed integrally therewith (i.e. not to bedetached by a user), the drug delivery device comprising a drugreservoir or means for receiving a drug reservoir, the drug reservoircomprising an outlet portion, a detachable cap adapted to cover the drugreservoir outlet portion in a mounted position, and drug expelling meanscomprising dose setting means allowing a user to set a dose amount ofdrug to be expelled. The logging device further comprises electroniccircuitry comprising sensor means adapted to capture a property valuerelated to a dose amount of drug expelled from a reservoir by theexpelling means during an expelling event when the logging device hasbeen attached to a drug delivery device, processor means adapted todetermine dose amounts based on captured property values, memory meansadapted to store at least one dose amount, display means adapted todisplay (i) a determined dose amount and/or a time value, and (ii) awarning message, and switch means adapted to be operated, when thelogging device has been attached to a drug delivery device or is formedintegrally therewith, between an off-state when the caps is in themounted position and an on-state when the cap has been detached. A givendose amount may be stored in the memory in the form of e.g. the “native”detected property representing an amount of drug or as a calculatedamount of drug. In such a device the sensor means is turned on when theswitch is operated from the off- to the on-state, the sensor means isturned off when the switch is operated from the on- to the off-state,the sensor means is turned off automatically when a predetermined amountof time has lapsed, and the display means is turned on to display awarning message when the switch is operated from the on- to theoff-state and the sensor means has been turned off automatically, thewarning message indicating to a user that an expelled dose may not havebeen captured.

Correspondingly, in a first specific aspect of the invention a loggingdevice adapted to be releasably attached to a drug delivery device isprovided, the drug delivery device comprising a drug reservoir or meansfor receiving a drug reservoir, the drug reservoir comprising an outletportion, a detachable cap adapted to cover the drug reservoir outletportion in a mounted position, drug expelling means comprising dosesetting means allowing a user to set a dose amount of drug to beexpelled, and electronic circuitry adapted to create a log of expelleddose amounts of drug. The electronic circuitry comprises sensor meansadapted to capture a property value related to a dose amount of drugexpelled from a reservoir by the expelling means during an expellingevent when the logging device has been attached to a drug deliverydevice, processor means adapted to determine dose amounts based oncaptured property values, memory means adapted to store at least onedose amount, display means adapted to display a determined dose amountand/or a time value as well as a warning message, the electroniccircuitry further comprising switch means. A time value may beassociated with each stored dose amount. With the logging deviceattached to a drug delivery device the switch means is adapted to beoperated between an off-state when the cap is in the mounted positionand an on-state when the cap has been detached. In such an arrangementthe sensor means is turned on when the switch is operated from the off-to the on-state, the sensor means is turned off when the switch isoperated from the on- to the off-state, the sensor means is turned offautomatically when a predetermined amount of time has lapsed, and thedisplay means is turned on to display a warning message when the switchis operated from the on- to the off-state and the sensor means has beenturned off automatically, the warning message indicating to a user thatan expelled dose may not have been captured.

The predetermined amount of time is initially counted from when the capis removed, however, the counter may be reset when a given event isdetected, e.g. a successful logging of an expelled dose of drug, thisallowing a user to divide a given dose into split doses without “timeconstraints”.

As appears, an add-on device mounted to a pen device is turned on whenthe cap is removed, and after a given amount of time in inactivity theadd-on device is turned off automatically, this to save energy. However,after this has happened the user may take a dose of drug which is thennot detected as the add-on device is only turned on when the cap isremoved. By providing a warning message when the cap is re-mounted afterthe sensor means has been turned off automatically, the warning messageindicates to a user that an expelled dose may not have been captured,this allowing the user to take appropriate action if a dose was actuallyexpelled.

When the cap is re-mounted after a “normal” use event, the display meansmay display a determined dose amount together with a time value.Alternatively, only a dose amount or only a time value may be shown. Thetime may be a real time value or the time since a given dose amount wasstored.

In an exemplary embodiment the display means is turned on for apredetermined amount of time to display a message when the switch isoperated from the on- to the off-state, the message being in the form ofthe last determined dose amount and/or a time value when the display isturned on without the sensor means having been turned off automatically,or the warning message when the display is turned on with the sensormeans being turned off automatically. To save energy the sensor meansmay be turned on with a time delay when the switch is operated from theoff- to the on-state, this allowing the user to check the latest logvalue without turning on the sensor system.

Addressing the situation in which he user desires to split a given(large) dose, stored dose amounts determined within a given time periodmay be combined to a single combined dose amount. The given time periodmay be initiated by a detected expelling event taking place a givenamount of time after a previous detected expelling event, or after agiven detected action.

When two or more dose amounts are determined within a given time periodthey may be combined automatically, or the user may be prompted toaccept that the two or more dose amounts determined within a given timeperiod are combined. Combined amounts may be indicated as such in thedisplay. A determined dose amount below a given value, e.g. below 2 or 3units of insulin, may be estimated to be a priming or an air shot andthus not combined as a log entry. When a combined dose amount iscalculated and stored the individual doses may remain stored andsubsequently retrieved when desired. The stored and retrievable data maycomprise all determined dose amounts, i.e. including air shots and doseamounts determined in a sensor time-out event but before the sensorswere turned off. A time value may be associated with each stored doseamount. For a combined dose e.g. the last time value may be used. Theelectronic circuitry may comprise transmitter means adapted to transmitstored data to an external receiver, e.g. by means of NFC or Bluetooth.

The sensor means may be adapted to capture a property value in the formof an amount of rotation of a magnetic member arranged in the drugdelivery device, the amount of rotation of the magnetic membercorresponding to the amount of drug expelled from a reservoir by theexpelling means. The electronic circuitry may comprise transmitter meansadapted to transmit stored data to an external receiver, e.g. by meansof NFC.

The above-described logging device may be provided in combination with adrug delivery device, thereby forming a drug delivery system, the drugdelivery device comprising a drug reservoir or means for receiving adrug reservoir, the drug reservoir comprising an outlet portion, adetachable cap adapted to cover the drug reservoir outlet portion in amounted position, and drug expelling means comprising dose setting meansallowing a user to set a dose amount of drug to be expelled, wherein thelogging device is releasably attachable to the drug delivery device.

In an exemplary embodiment the drug delivery device further comprises anidentifier, e.g. a colour or in the form of a barcode, representinginformation for the specific drug type contained in the reservoir or thespecific drug delivery device, with the logging device furthercomprising means for capturing information from the identifier, whereinthe electronic circuitry is adapted to create a log for a givenidentifier.

In a further specific aspect of the invention a drug delivery system isprovided, comprising a drug reservoir or means for receiving a drugreservoir, the drug reservoir comprising an outlet portion, a detachablecap adapted to cover the drug reservoir outlet portion in a mountedposition, drug expelling means comprising dose setting means allowing auser to set a dose amount of drug to be expelled, electronic circuitrycomprising sensor means adapted to capture a property value related tothe dose amount of drug expelled from the reservoir by the expellingmeans during an expelling event, processor means adapted to determinedose amounts based on captured property values, memory means adapted tostore at least one dose amount, display means adapted to display adetermined dose amount and/or a time value, and a warning message, andswitch means adapted to be operated between an off-state when the cap isin the mounted position and an on-state when the cap has been detachedfrom the system, wherein the sensor means is turned on when the switchis operated from the off- to the on-state, the sensor means is turnedoff when the switch is operated from the on- to the off-state, thesensor means is turned off automatically when a predetermined amount oftime has lapsed, and the display means is turned on to display a warningmessage when the switch is operated from the on- to the off-state andthe sensor means has been turned off automatically, the warning messageindicating to a user that an expelled dose may not have been captured.

The system may be in the form of an integrated drug delivery devicecomprising the drug reservoir or means for receiving a drug reservoir,the drug expelling means, and the electronic circuitry. The integrateddevice may be provided with the above-described features of a separatelogging device.

In order to capture a property value related to a dose amount of drugexpelled a number of technologies could be used. For example, for anintegrated arrangement capture could be based on galvanic contacts,optical sensors or magnetic sensors. Indeed, for an external attachablelogging device the same principles could be used, however, by usingmagnetic detection it would be possible to detect movements inside thedelivery device without having to provide openings or contacts in thehousing wall. For a given expelling mechanism a number of componentswill normally be moved corresponding to an expelled amount of drug, e.g.a piston rod will move axially and a drive member for moving the pistonrod may rotate. Correspondingly, a property value could be either axialdisplacement or amount of rotation, or a combination of both. Forexample, if a given component may rotate more than 360 degrees in orderto expel a given dose, the amount of rotation may be captured bycounting increments or, alternatively, by determining the rotationalposition of the rotating component and combine it with informationrelating to the number of full rotations or the axial position of anaxially moved component.

In the context of the present application and as used in thespecification and the claims, the term processor means covers anycombination of electronic circuitry suitable for providing the specifiedfunctionality, e.g. processing and storing data as well as controllingall connected input and output devices. A processor will typicallycomprise one or more CPUs or micro-processors which may be supplementedby additional devices for support, memory or control functions. Forexample, in case a communication interface is provided (e.g. wireless),the transmitter and receiver may be fully or partly integrated with aprocessor, or may be provided by individual units. Each of thecomponents making up the processor circuitry may be special purpose orgeneral purpose devices. The term display means covers any type ofdisplay capable of visually providing the specified functionality, e.g.a LCD or OLED.

As used herein, the term “insulin” is meant to encompass anydrug-containing floss able medicine capable of being passed through adelivery means such as a cannula or hollow needle in a controlledmanner, such as a liquid, solution, gel or fine suspension, and whichhas a blood glucose controlling effect, e.g. humans insulin andanalogues thereof as well as non-insulins such as GLP-1 and analoguesthereof. In the description of exemplary embodiments reference will bemade to the use of insulin.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following exemplary embodiments of the invention will bedescribed with reference to the drawings, wherein

FIGS. 1A and 1B show a pen-formed drug delivery device with anelectronic logging module,

FIG. 2 shows the interior of a logging module,

FIG. 3 shows a display with all segments active,

FIG. 4 shows a flowchart with display readings during differentoperational states, and

FIG. 5 shows a drug delivery pen provided with a logging module and incommunication with a smartphone.

In the figures like structures are mainly identified by like referencenumerals.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

When in the following terms such as “upper” and “lower”, “right” and“left”, “horizontal” and “vertical” or similar relative expressions areused, these only refer to the appended figures and not necessarily to anactual situation of use. The shown figures are schematic representationsfor which reason the configuration of the different structures as wellas their relative dimensions are intended to serve illustrative purposesonly. When the term member or element is used for a given component itgenerally indicates that in the described embodiment the component is aunitary component, however, the same member or element may alternativelycomprise a number of sub-components just as two or more of the describedcomponents could be provided as unitary components, e.g. manufactured asa single injection moulded part. The term “assembly” does not imply thatthe described components necessarily can be assembled to provide aunitary or functional assembly during a given assembly procedure but ismerely used to describe components grouped together as beingfunctionally more closely related.

FIGS. 1A and 1B show a pen-formed drug delivery device 200 on which anelectronic logging module 100 is mounted. In the present context thedevice represents a “generic” drug delivery device providing a specificexample of a device in combination with which embodiments of the presentinvention is intended to be used or which can form a basis for aspectsof the present invention.

More specifically, the logging module 100 comprises a body portion 110and a ring-formed portion 120 allowing the module to be mounted on agenerally cylindrical pen device. The body portion comprises electroniccircuitry and sensor means allowing a property to be detectedrepresenting an amount of drug being expelled from the cartridge, aswell as a display 130 for displaying data to a user. The ring portioncomprises coupling means allowing the module to be securely andcorrectly mounted on the pen body. The electronic circuitry and thesensor means may in part be arranged in the ring portion. Depending onthe sensor means provided in the logging module and the property to bedetected, the drug delivery device may have to be adapted specificallyto allow the given property to be detected. For example, the drugdelivery device may be provided with a magnet rotating during doseexpelling, the logging module being adapted to detect the amount ofrotation, see below.

The pen device 200 comprises a cap part 207 and a main part having aproximal body or drive assembly portion with a housing 201 in which adrug expelling mechanism is arranged or integrated, and a distalcartridge holder portion in which a drug-filled transparent cartridge213 with a distal needle-penetrable septum is arranged and retained inplace by a non-removable cartridge holder attached to the proximalportion, the cartridge holder having openings allowing a portion of thecartridge to be inspected as well as distal coupling means 215 allowinga needle assembly to be releasably mounted. The cartridge is providedwith a piston driven by a piston rod forming part of the expellingmechanism and may for example contain an insulin, GLP-1 or growthhormone formulation. A proximal-most rotatable dose member 280 serves tomanually set (or dial) a desired dose of drug shown in display window202 and which can then be expelled when the button 290 is actuated.Depending on the type of expelling mechanism embodied in the drugdelivery device, the expelling mechanism may comprise a spring as in theshown embodiment which is strained during dose setting and then releasedto drive the piston rod when the release button is actuated.Alternatively the expelling mechanism may be fully manual in which casethe dose member and the actuation button moves proximally during dosesetting corresponding to the set dose size, and then is moved distallyby the user to expel the set dose.

FIGS. 1A and 1B show a drug delivery device of the pre-filled type, i.e.it is supplied with a pre-mounted cartridge and is to be discarded whenthe cartridge has been emptied. In alternative embodiments the drugdelivery device may be designed to allow a loaded cartridge to bereplaced, e.g. in the form of a “rear-loaded” drug delivery device inwhich the cartridge holder is adapted to be removed from the device mainportion, or alternatively in the form of a “front-loaded” device inwhich a cartridge is inserted through a distal opening in the cartridgeholder which is non-removably attached to the main part of the device.

Turning to FIG. 2 an exemplary embodiment of a logging module 300 isshown in which the exterior housing has been removed to reveal theinterior design and components. The module comprises a main body 310having a generally cylindrical ring-formed portion 320 and a bodyportion 330 together forming a chassis on which the majority of theelectronic circuitry is mounted. The main body is formed from a LDSpolymer whereby integrated wiring can be achieved by using LDS (LaserDirect Structuring) technology, the polymer having elastic propertiesallowing a flexible hinged latch to be formed integrally. Alternatively,the electronics including the sensors may be mounted on a flexible PCBwhich then is mounted on the main body 310 using e.g. metal clips. As afurther alternative a flexible PCB may be mounted by fully or partlybonding it to a chassis component using double-sided adhesive, thisallowing an accurate, reliable and compact design. The ring portioncomprises an inner generally cylindrical surface adapted to be mountedon a drug delivery pen body as well as a pair of opposed integrallyformed coupling structures 321 adapted to engage corresponding couplingstructures on the pen device to assure that the module is securelymounted. The distal part of the ring portion has a larger diameter witha distally facing circumferential stop surface 329 adapted to receiveand engage a cap when the module is mounted on a pen, see below.

The inner ring surface and the outer pen body surface may be in eitherform-fitting or slight frictional engagement. Each coupling structure onthe module is in the form of a latch having a proximal portion 323, adistal portion 324 and a central portion, the latter being pivotallyconnected to the ring portion by integrally formed flexible hinges 325allowing the latch to pivot a few degrees corresponding to acircumferential axis. By this arrangement the distal latch portion movesinwards when the proximal portion is moved outwards and vice versa. Theproximal latch portions each comprises an inner protrusion 326 adaptedto engage a corresponding coupling structure on the pen device (e.g.protrusions otherwise used for attachment of the cap) and the distallatch portions each comprises a protrusion 327 adapted to frictionallyengage the cap outer surface when a cap is mounted after use.Alternatively the cap outer surface may be provided with coupling means,e.g. a circumferential groove, allowing the cap to engage the loggingmodule by snap action. As appears for the shown embodiment, when thelogging module is mounted on the drug delivery pen body, the capattaches to the logging module and not the pen body. In alternativeembodiments, the logging module may allow the cap to be attacheddirectly to the pen body. To assure correct rotational mounting of themodule on the pen the shown module is provided with a funnel-shaped slotadapted to axially engage a corresponding protrusion on the pen. In theshown embodiment of FIG. 1A a protrusion is provided on the pencartridge holder 210 and arranged opposite the pen display window 202,the electronic display 130 thereby being arranged next to the pendisplay window when the module is mounted on a pen. The interactionsbetween the logging module, the pen body and the cap will be describedin greater detail below.

On the body portion 330 the majority of the electronic components 340including processors means with associated memory means, a displaymodule 341 with a display 360, a cap switch 342 for detecting thepresence of a mounted cap, a main switch (not shown) for detecting thatthe logging module is mounted on a pen body, and an energy source 343are mounted. The latter may be in the form of a non-replaceable devicelife-time “battery”, a replaceable battery or in the form of arechargeable battery. In the shown embodiment the LCD is of atraditional stiff type to be covered by a separate display window,however, alternatively a flexible LCD may be bonded directly to atransparent plastic cover providing a compact and robust design. Inaddition to the LCD a sound generator, e.g. a piezo beeper, may beprovided to signal different states and/or error conditions to the user.

In the shown embodiment the logging module is provided with a firstsensor assembly comprising three “compass” sensor units 345 mountedequidistantly on the ring portion 320, each sensor unit being in theform of a magnetometer adapted to measure a magnetic field correspondingto three axes. Another type and number of sensors arranged in anotherpattern may be used. In the shown embodiment the sensor system isdesigned to detect the amount of rotation of a magnetic member arrangedinside the drug delivery device for which the logging module has beenspecifically designed, such a system being described in greater detailin PCT application EP 2014/056724 which is hereby incorporated byreference.

Further sensors may be provided allowing e.g. the type of the device(and thereby the drug) to be recognized, this being relevant if e.g. thedrug delivery device is sold with a given drug in differentconcentrations such as insulin with 100 or 200 IU per ml. Alternatively,the logging module and the drug delivery device may be provided withmechanical coding means allowing a given logging module to be mountedonly on a drug delivery device specifically coded for use with thatlogging module.

In the shown embodiment the logging module comprises a ring-formedportion providing a bore adapted to receive a drug delivery device.Alternatively the ring may be open and provided with a releasableclosure member as disclosed in e.g. WO 2010/037828.

The logging module may be provided with user input means in the form ofe.g. one or more buttons (not shown) allowing the user to control themodule. The logging module may further be provided with transmissionmeans allowing data to be transmitted to or from the module, e.g. logdata may be transmitted to a user's smartphone by NFC or other wirelessmeans.

FIG. 3 shows an exemplary embodiment of a display 360 with all segmentsturned on. More specifically, the display comprises a dose size field361 for showing a dose size in IU, a time field 362 having a stopwatchformat HH:MM:SS, a “ready” symbol 363, and an “information” symbol 364.Exemplary use of the different display segments will be given below withreference to FIG. 4 .

Turning to FIG. 4 a flow-chart is shown in which different aspects ofthe logging module user interface is illustrated, i.e. how the differentfeatures of the logging module is used to provide a logging module whichin combination with a corresponding drug delivery device, e.g. as shownin FIGS. 1A and 1B, is both easy to use and energy efficient, the latterbeing a requirement especially in case the logging module is providedwith a non-exchangeable energy source intended to power the module forits intended life-time, e.g. three years of normal use for the averageuser.

When the mounted logging module is in its sleeping state the display 10is blank with no segments active. When the user removes the cap, therebyactivating the cap switch, the display 11 shows the “ready” symbolindicating that the sensor system is now turned on and the loggingmodule is ready to detect and store a dose to be expelled. During dosesetting and subsequent dose expelling the display 20 does not change butmerely shows the ready symbol. When the user after having expelled adose again attaches the cap the display 21 shows the expelled dose sizein the dose size field, e.g. 20 IU as shown, together with a time valuein the time field, e.g. 8 seconds as shown. As the latter has astopwatch configuration with a running second counter it is apparent tothe user that a “time-since-last-dose” is shown. At the same time theready symbol is turned off. After a given number of seconds, e.g. 20seconds, the display 22 is turned off. If the user later desires tocheck the latest log entry, i.e. dose size and time-since-last-dose, heor she activates the cap switch by moving the cap out of its mountedposition thereby turning on the ready symbol in the display 30 and movesit back to its mounted position, the display 31 showing the lastdetected dose size together with the actual time-since-last-dose, e.g.20 IU expelled 9 hours, 11 minutes and 29 seconds ago. To save energythe sensor system may be turned on with a delay of e.g. a few seconds,this allowing the user to check the latest log entry without the sensorsystem being turned on.

To safe-guard low energy consumption the sensor system will time out andturn off after a certain amount of time, e.g. 5 minutes, after which theready symbol in the display 40 is turned off. The logging module may bedesigned to re-start the timer for each successful detection of anexpelled dose, this allowing the user time to split a given dose intotwo or more doses. Although the blank display indicates to the user thatthe sensor system has been turned off, the drug delivery device can beused as usual to set and expel a desired dose, however, the sensorsystem will remain turned off and the display 41 will remain blank.However, in order to remind the user that any dose that may have beenexpelled during a time-out period has not been logged, the display 42will turn on the information “i” symbol. As appears, whether or not adose has been expelled, the user is presented with the “i” symbol whenthe cap is mounted again after a sensor time-out event. If the loggingmodule is provided with an audible alarm, e.g. a beeper, the alarm maybe sounded as well. In case the time-out appears after a successfuldetection of an expelled dose, the “i” will still be shown when the capis put on, however, the detected dose has been stored and can berecalled as described below. Alternatively the “i” symbol may bereplaced with a symbol more directly indicating an error condition.

With reference to FIG. 3 two exemplary logging module features have beendescribed, i.e. (i) display showings during normal use, and (ii) displayshowing after a sensor time-out event.

Each of the two features may be implemented alone or in combination fora given logging module.

In addition to the above-described use scenarios, the display symbolsand number fields can be used in additional ways. For example, the “i”symbol may be used in combination with a value shown in the dose sizefield to generate a number of codes, e.g. to indicate an error duringdose sensing, a low battery condition or information in respect of datatransfer, see below. Further, if the logging module is adapted tocombine split doses (see EP 2014/056727) the “i” may be used to indicatethat doses have been combined.

FIG. 5 shows a drug delivery pen 200 provided with a logging module 100of the type described above with reference to FIGS. 1-4 and arrangednext to a smartphone 400 configured to receive logging data from thelogging module via wireless communication, e.g. NFC. As described above,the logging module is provided with a display configured to indicate thesize of the last dose and the time since the last dose using thestopwatch display mode.

In order to communicate with the logging module the smartphone has beenprovided with specific “insulin diary” software. When the software isactivated to initiate data transfer the smartphone NFC transmitter willtransmit specific code which will wake up any nearby logging modulewhich will then retransmit a unique code identifying the specificmodule. If a specific code is received for the first time the user isasked to confirm pairing and is asked to select from a list the givendrug that should be associated with the given logging module, e.g. “Mix30” as shown. Alternatively, the logging module may be designed to workwith only one type of pen containing only one specific type of drug, thetype of drug being transmitted during initial pairing, or the loggingmodule may be provided with the ability to identify different types ofpens and thus different types of drugs. In the shown embodiment log datafrom a logging module associated with a Mix 30 insulin has beentransferred. Transfer may be controlled entirely by the smartphone, thelogging module merely transmitting data when requested to do so. Forexample, when controlled to transfer logging data the logging module maytransmit the entire memory content each time, e.g. 30 logging events,the smartphone being adapted to identify new log entries since lasttransfer. The stored logging data may comprise all determined doseamounts, i.e. including air shots and dose amounts determined in asensor time-out event but before the sensors were turned off.

When data has been successfully transmitted this may be indicated on thesmartphone as well as on the logging module. In the exemplary userinterface the user can toggle back and forth between different dayviews, each day view showing the different amounts of drug deliveredtogether with a real time value. In FIG. 5 on a given day 401 first andsecond amounts 402 of Mix 30 has been delivered with the time and amountshown for each delivery. It may be indicated if a given dose amount isbased on combined dose amounts. To avoid having a real time clock in thelogging module time information for each log entry may be generated bythe smartphone based on relative time information provided by thelogging module.

With reference to FIGS. 1-5 an electronic logging module adapted to bemounted on a performed drug delivery device has been described, however,the components of the module may alternatively be incorporated in a drugdelivery device forming a unitary device. As such a device will compriseonly a single housing the over-all volume may be reduced.

In the above description of exemplary embodiments, the differentstructures and means providing the described functionality for thedifferent components have been described to a degree to which theconcept of the present invention will be apparent to the skilled reader.The detailed construction and specification for the different componentsare considered the object of a normal design procedure performed by theskilled person along the lines set out in the present specification.

The invention claimed is:
 1. A logging device releasably attached to adrug delivery device, the drug delivery device comprising a drugreservoir or a structure for receiving the drug reservoir, the drugreservoir comprising an outlet portion, a detachable cap adapted tocover the drug reservoir outlet portion in a mounted position, and adrug expeller comprising a dose setter allowing a user to set a doseamount of a drug to be expelled, the logging device comprising:electronic circuitry comprising: a sensor adapted to capture a propertyvalue related to the dose amount of the drug expelled from the drugreservoir by the drug expeller during an expelling event when thelogging device has been attached to the drug delivery device, aprocessor adapted to determine dose amounts based on the capturedproperty values, a memory adapted to store at least one dose amount, adisplay adapted to display a determined dose amount and/or a time value,and a warning message, and a switch adapted to be operated by thedetachable cap, when the logging device has been attached to the drugdelivery device, between an off-state when the detachable cap is in themounted position and an on-state when the detachable cap has beendetached, wherein: the sensor is turned on when the switch is operatedfrom the off-state to the on-state when the detachable cap is removed,the sensor is turned off when the switch is operated from the on-stateto the off-state when the detachable cap is remounted, the sensor isturned off automatically when a predetermined amount of time has lapsed,and the display is turned on to display the warning message when theswitch is operated from the on-state to the off-state and when thesensor has been turned off automatically, the warning message indicatingto the user that the expelled dose may not have been captured.
 2. Thelogging device as in claim 1, wherein: the display is turned on for apredetermined amount of time to display a message when the switch isoperated from the on-state to the off-state, the message being in theform of: a last determined dose amount and/or a time value when thedisplay is turned on without the sensor having been turned offautomatically, or the warning message when the display is turned on withthe sensor being turned off automatically.
 3. The logging device as inclaim 1, wherein stored dose amounts determined within a given timeperiod are combined to a single combined dose amount, and the given timeperiod is initiated by a detected expelling event taking place: a givenamount of time after a previously detected expelling event, or after agiven detected action.
 4. The logging device as in claim 3, wherein twoor more dose amounts determined within the given time period arecombined automatically.
 5. The logging device as in claim 3, wherein theuser is prompted to accept that two or more dose amounts determinedwithin the given time period are combined.
 6. The logging device as inclaim 3, wherein a determined dose amount below a given value isestimated to be a priming or air shot and is not combined with anotherlog entry.
 7. The logging device as in claim 1, wherein a log comprisesa time value associated with each stored dose amount.
 8. The loggingdevice as in claim 1, wherein the sensor is adapted to capture theproperty value in the form of an amount of rotation of a magnetic memberarranged in the drug delivery device, the amount of rotation of themagnetic member corresponding to the dose amount of the drug expelledfrom the drug reservoir by the drug expeller.
 9. The logging device asin claim 1, wherein the sensor is turned on with a time delay when theswitch is operated from the off-state to the on-state.
 10. A drugdelivery system, comprising: a drug reservoir or a structure forreceiving the drug reservoir, the drug reservoir comprising an outletportion; a detachable cap adapted to cover the drug reservoir outletportion in a mounted position; a drug expeller comprising a dose setterallowing a user to set a dose amount of a drug to be expelled; andelectronic circuitry comprising: a sensor adapted to capture a propertyvalue related to the dose amount of the drug expelled from the drugreservoir by the drug expeller during an expelling event, a processoradapted to determine dose amounts based on the captured property values,a memory adapted to store at least one dose amount, a display adapted todisplay a determined dose amount and/or a time value, and a warningmessage, and a switch operable by the detachable cap between anoff-state when the detachable cap is in the mounted position and anon-state when the detachable cap has been detached from the drugdelivery system, wherein: the sensor is turned on when the switch isoperated from the off-state to the on-state when the detachable cap isremoved, the sensor is turned off when the switch is operated from theon-state to the off-state, the sensor is turned off automatically when apredetermined amount of time has lapsed, and the display is turned on todisplay the warning message when the switch is operated from theon-state to the off-state and when the sensor has been turned offautomatically, the warning message indicating to the user that theexpelled dose may not have been captured.
 11. The drug delivery systemas in claim 10, wherein the system is in the form of a drug deliverydevice comprising: the drug reservoir, the drug expeller, and theelectronic circuitry.
 12. The drug delivery system as in claim 10,wherein the sensor is adapted to capture the property value in the formof an amount of rotation of a magnetic member arranged in the drugdelivery device, the amount of rotation of the magnetic membercorresponding to the dose amount of the drug expelled from the drugreservoir by the drug expeller.
 13. The drug delivery system as in claim10, wherein two or more dose amounts determined within a given timeperiod are combined automatically.
 14. The drug delivery system as inclaim 10, the drug delivery device further comprising: an identifierrepresenting information for a specific drug type contained in the drugreservoir or a specific drug delivery device, and a logging device forcapturing information from the identifier, wherein the electroniccircuitry is adapted to create a log for a given identifier.
 15. Alogging device releasably attached to a drug delivery device, the drugdelivery device comprising a drug reservoir or a structure for receivingthe drug reservoir, the drug reservoir comprising an outlet portion, adetachable cap adapted to cover the drug reservoir outlet portion in amounted position, and a drug comprising a dose setter allowing a user toset a dose amount of a drug to be expelled, the logging devicecomprising: electronic circuitry comprising: a sensor adapted to capturea property value related to the dose amount of the drug expelled fromthe drug reservoir by the drug expeller during an expelling event whenthe logging device has been attached to the drug delivery device, aprocessor adapted to determine dose amounts based on the capturedproperty values, a memory adapted to store at least one dose amount, adisplay adapted to display a determined dose amount and/or a time value,and a warning message, and a switch adapted to be operated between anoff-state and an on-state, wherein: the sensor is turned on when theswitch is operated from the off-state to the on-state, the sensor isturned off when the switch is operated from the on-state to theoff-state, the sensor is turned off automatically when a predeterminedamount of time has lapsed, and the display is turned on to display thewarning message when the switch is operated from the on-state to theoff-state and when the sensor has been turned off automatically, thewarning message indicating to the user that the expelled dose may nothave been captured.
 16. A drug delivery system, comprising: a drugreservoir or a structure for receiving the drug reservoir, the drugreservoir comprising an outlet portion; a detachable cap adapted tocover the drug reservoir outlet portion in a mounted position; a drugexpeller comprising a dose setter allowing a user to set a dose amountof a drug to be expelled; and electronic circuitry comprising: a sensoradapted to capture a property value related to the dose amount of thedrug expelled from the drug reservoir by the drug expeller during anexpelling event, a processor adapted to determine dose amounts based onthe captured property values, a memory adapted to store at least onedose amount, a display adapted to display a determined dose amountand/or a time value, and a warning message, and a switch operablebetween an off-state and an on-state, wherein: the sensor is turned onwhen the switch is operated from the off-state to the on-state, thesensor is turned off when the switch is operated from the on-state tothe off-state, the sensor is turned off automatically when apredetermined amount of time has lapsed, and the display is turned on todisplay the warning message when the switch is operated from theon-state to the off-state and when the sensor has been turned offautomatically, the warning message indicating to the user that theexpelled dose may not have been captured.
 17. A method of capturing andorganizing drug delivery dose data comprising: providing a drug deliverysystem, comprising: a drug reservoir or a structure for receiving thedrug reservoir, the drug reservoir comprising an outlet portion; adetachable cap adapted to cover the drug reservoir outlet portion in amounted position; a drug expeller comprising a dose setter allowing auser to set a dose amount of a drug to be expelled; and electroniccircuitry comprising: a sensor adapted to capture a property valuerelated to the dose amount of the drug expelled from the drug reservoirby the drug expeller during an expelling event, a processor adapted todetermine dose amounts based on the captured property values, a memoryadapted to store at least one dose amount, a display adapted to displaya determined dose amount and/or a time value, and a warning message, anda switch operable between an off-state and an on-state, wherein: thesensor is turned on when the switch is operated from the off-state tothe on-state, the sensor is turned off when the switch is operated fromthe on-state to the off-state, the sensor is turned off automaticallywhen a predetermined amount of time has lapsed, and the display isturned on to display the warning message when the switch is operatedfrom the on-state to the off-state and when the sensor has been turnedoff automatically, the warning message indicating to the user that theexpelled dose may not have been captured.